Lilly’s Zepbound tops Wegovy for weight loss in head-to-head trial

By Patrick Wingrove

(Reuters) -Eli Lilly said on Wednesday patients taking its obesity drug Zepbound lost 47% more weight than those who were given Novo Nordisk’s Wegovy in the first large, head-to-head trial of the highly in-demand rival medicines.

The U.S. drugmaker’s shares rose 2.5% to a three-week high, adding some $19 billion to Lilly’s market value and taking it over $790 billion, while Novo Nordisk’s Copenhagen-listed shares fell as much as 1.8% and were down 0.5% at 1547 GMT.

In the 751-person trial sponsored by Lilly, Zepbound helped patients lose an average of 20.2% of their weight after 72 weeks compared to 13.7% for the group treated with Wegovy, Lilly said.

The data comparing the wildly popular medicines shows for the first time that when trial parameters are the same, Lilly’s drug, which mimics two gut hormones, is more effective for weight loss than Wegovy with its single mode of action.

Participants were either obese or overweight and had an additional related health issue such as obstructive sleep apnea or heart disease. None of the trial subjects had diabetes.

Before the data was published, BMO Capital Markets analyst Evan Seigerman said the market expects Lilly’s drug to show superior efficacy.

A confirmation, however, “could be a differentiator when the market matures in the long-term and physicians are not capacity constrained” but can select a medicine more easily by efficacy alone and not availability, he wrote.

Doctors had been prescribing the obesity drugs based on whichever was available to patients at the pharmacy given intermittent supply shortages.

‘SET A HIGH BAR’

Novo Nordisk is banking on a novel drug in development called CagriSema with a dual mode of action to regain an edge on efficacy over Lilly. Its late-stage trial results, which the Danish drugmaker said could result in 25% weight loss, are expected this month.

Lukas Leu, fund manager at healthcare-focused Bellevue Asset Management in Switzerland, said the Wegovy-to-Zepbound comparison was broadly in line with expectations but underscored the pressure on weight-loss pioneer Novo.

“Lilly has set a high bar with Zepbound and it is expected to also have trial data for an oral drug, also in Phase 3, during the first half next year,” said Leu, referring to experimental daily pill orforglipron.

“It’s extremely important for Novo to show good CagriSema data,” he added.

U.S. approvals for Zepbound and Wegovy were based on separate trials in which the Lilly drug helped patients lose more than 22% of their weight after 72 weeks, while Wegovy led to 15% weight loss after 68 weeks.

Lilly said it would publish full results from the trial in a peer-reviewed journal and present them at a medical meeting next year.

Novo Nordisk said it will wait for the complete data, including the distribution of treatment doses in the two groups, once it is peer-reviewed and published.

It said Wegovy is the only obesity drug shown to reduce the risk of heart attack or stroke. The companies have been racing to get the drugs approved to treat other ailments to help improve acceptance by insurers and governments.

The U.S. approved Wegovy as a treatment for heart disease in March, while Zepbound is expected to get the green light as a treatment for obstructive sleep apnea.

The new results may persuade insurers in the U.S. and cost-conscious health authorities in Europe to give preferential coverage to Zepbound over Wegovy.

An analysis of health records and other data published by the medical journal JAMA Internal Medicine earlier this year showed Zepbound led to faster and greater weight loss than Wegovy.

Both drugs are sold in the U.S. under different brand names – Novo’s Ozempic and Lilly’s Mounjaro – to treat type 2 diabetes.

(Reporting by Patrick Wingrove in New York and additional reporting by Manas Mishra in Bengaluru, Ludwig Burger in Frankfurt; Editing by Bill Berkrot)